1. Field of the Invention
The present invention relates to the field of radio frequency identification (RFID) systems. In particular, the present invention relates specifically to structures for supporting RFID antennas and/or RFID readers.
2. Description of the Known Art
As will be appreciated by those skilled in the art, radio frequency identification (RFID) has become a prevalent method for identifying products. Namely, manufacturers and large-scale retailers have increasingly implemented the use of RFID technology to track product locations in route to retail outlets, within storage locations, and within retail stores. RFID readers are used to receive data transmitted from RFID tags. The data transmitted by the tag may provide identification or location information, or specifics about the product tagged, such as price, color, date of purchase, etc. Art relevant to this field can be found in class 235, subclasses 435, 439, 451 and class 343, subclasses 700, 874, 875. Patents disclosing information relevant to RFID technology include U.S. Pat. No. 5,347,263, issued to Carroll et al. on Sep. 13, 1994; U.S. Pat. No. 5,430,441, issued to Bickley et al. on Jul. 4, 1995; U.S. Pat. No. 5,446,447, issued to Carney et al. on Aug. 29, 1995; U.S. Pat. No. 5,519,381, issued to Marsh et al. on May 21, 1996; U.S. Pat. No. 6,392,544, issued to Collins et al. on May 21, 2002; U.S. Pat. No. 6,396,438, issued to Seal on May 28, 2002; U.S. Pat. No. 6,509,836, issued to Ingram on Jan. 21, 2003; U.S. Pat. No. 6,747,560, issued to Stevens on Jun. 8, 2004; and U.S. Pat. No. 6,903,656, issued to Lee on Jun. 7, 2005. Each of these patents is hereby expressly incorporated by reference in their entirety.
RFID systems usually include at least one radio frequency antenna and a reader. During a typical usage, the RFID system transmits a radio frequency at a certain frequency or within a certain frequency range towards an RFID tag. An RFID tag typically includes a chip (often smaller than a pin head) and an antenna portion. The energy in the radio waves transmitted onto the tag may be used to “excite” or energize the tag. The chip is often programmed with a globally unique identification (GUID) number, and upon exciting the tag, the GUID number is emitted from the tag in the form of radio waves. A receiving antenna of the RFID system receives the radio waves emitted from the tag, and a reader device extracts the GUID number from the signal in the tag's emitted radio waves. This GUID number may then be correlated to a product or item in a database. The transmitting antenna may be separate from the receiving antenna (e.g., pitch-catch configuration), or they may be one and the same (i.e., transmit and receive with same antenna).
RFID systems may have a variety of forms and configurations for different applications, for example: hand held devices such as a wand; free standing structures monitoring theft detection in retail stores or warehouse inventory tracking; and fixed structures attached to or extending from a building, such as building access locks and toll tag structures above a toll road. In most existing warehouse usages of RFID systems, some or all of the RFID components (e.g., antenna, reader) of the system are exposed. In a warehouse, there are typically forklifts and carts regularly moving boxes and crates of products past and near the RFID system. Hence, there is a likelihood that the exposed RFID components may be bumped, hit, or damaged during regular operation of the warehouse. Many times, an RFID system is tuned and an RFID antenna is set at a particular position and angle for optimum ability to read tags passing thereby. A movement or repositioning of such an antenna in a tuned system may reduce the performance of the system or even render the system inoperable. As the reliance on and usage of RFID tags and systems increases, the demand for rugged and reliable RFID systems is likely to increase. Hence, a need exists for an RFID system that provides increased protection of the RFID components in the system, but without significantly compromising the ability to tune the system, without significantly hindering the performance of the system, and without consuming a significant amount of warehouse space. Furthermore, it would be preferable to provide such a system without it being overly complex and expensive.
Patents disclosing information relevant to housings for RFID readers include U.S. Pat. No. 5,378,880, issued to Eberhardt on Jan. 3, 1995; U.S. Pat. No. 6,445,297, issued to Nicholson on Sep. 3, 2002; U.S. Pat. No. 7,036,734, issued to Baker on May 2, 2006; and U.S. Pat. No. 7,411,507, issued to Casden on Aug. 12, 2008. Each of these patents is hereby expressly incorporated by reference in their entirety.
U.S. Pat. No. 5,378,880, issued to Eberhardt on Jan. 3, 1995 entitled Housing structure for an access control RFID reader. The abstract describes a radio frequency proximity reader has a base plate housing portion that has an essentially rectangular shape with first and second opposed major surfaces and a centrally located bore. A cylindrical housing portion having a concentrically placed bore is attached to the base plate and extends substantially perpendicular to the first major surface, with the bores of the housing portions being substantially aligned. A radio frequency antenna including a cylindrical ferrite core having at least one concentrically wound coil is concentrically located within the cylindrical housing portion. A light emitting diode and a piezo buzzer are provided within the cylindrical housing portion adjacent the second major surface of the base plate. A cable electronically connects the reader to remotely located signal processing circuits. The base plate may be attached to a wall, whereby the first surface abuts the wall. A rectangular cover attached to the base plate covers the second major surface of the base plate. However, this housing structure fails to provide a stand-alone housing for an RFID reader for use in an open environment, such as a warehouse.
U.S. Pat. No. 6,445,297, issued to Nicholson on Sep. 3, 2002 entitled Modular RFID antenna system. The abstract describes a modular radio frequency identification device (RFID) antenna system including a plurality of modular RFID antenna segments that can be connected in multiple configurations to allow multi-directional RF communication with at least one RF tag that passes through the field of the antenna system from different directions and at different orientations and a configuration system to design, order, configure, test and operate the modular RFID antenna system. However, this modular system does not provide a resilient housing capable of withstanding hard impacts.
U.S. Pat. No. 7,036,734, issued to Baker on May 2, 2006 entitled Free standing column-shaped structure for housing RFID antennas and readers. The abstract explains an RFID system is provided, which includes one or more radio frequency antennas and a generally column-shaped structure. The generally column-shaped structure supports the antenna(s) therein. The structure may include a base portion, a frame portion, one or more paddle portions, and an external body portion. In such case, the frame portion is attached to and supported by the base portion. The frame portion extends along a longitudinal axis of the structure. Each paddle portion is pivotably coupled to the frame portion. Each paddle portion supports one or more antennas attached thereto. The hollow and elongated external body portion is attached to and supported by the base portion. The external body portion extends along the longitudinal axis. The frame portion, the paddle portion(s), and the antenna(s) are located within the external body portion. However, this structure fails to provide a bollard to reduce impacts to the portion and provide a notification access that allows for meaningful interpretation of the RFID reader alters.
U.S. Pat. No. 7,411,507, issued to Casden on Aug. 12, 2008 entitled Metal housing with integral antenna for RFID reader/writer. The abstract describes enhanced physical protection against vandalism for RFID reader/writer units is provided by a relatively thick metal front or housing which also functions as the antenna element of the reader/writer. The metal front is cut or slotted to define a radio frequency antenna integral with the metal front or housing for improved physical protection and good unshielded antenna function. However, this housing structure fails to provide a stand-alone housing for an RFID reader for use in an open environment such as a warehouse.
Thus, it may be seen that these prior art patents are very limited in their teaching and utilization, and an improved RFID reader housing is needed to overcome these limitations.